Anti sliver or anti tribe revolves around artifacts and enchantments. The pretty much harmonic sliver shuts those down. I have trouble with my brothers humility deck. I think some one tried a hivestone once but it didn't work since the sliver overlord just steals stuff for me. For some reason since as long as I can remember, Squirrels always beats Slivers. I can't explain it. I can't stand it either. That's just how it goes down. I'm 0 and 33 now.